Is there a simple way to downsample songs without re-adding them to the library?

Question

Hello all, here's my problem.
I have a library of about 60 days worth of music, 176GB in size. I have most of my songs in 256kbps and above, with a vast amount in 320mp3. I use the Date Added sorting a lot and I do not want to mess up the chronological system in any way. Basically, the way my "history" looks now should be unaffected. There is a very large amount of playlists too, so no song should have to be manually re-added to each playlist it used to be in. The play count and ratings are  also vital for me, so they cannot be lost.
Now, for the actual question, is there a way where I could select which songs can I downsample to a lower-resolution, without having to re-add it to the library, but instead substitute it for the previous file? Again, the file cannot be simply re-added but it has to replace the file that the library links to in order not to lose all the precious information.
If I could do all of this within iTunes, the better.
Any help is appreciated!

Answer 1

No.  In down sampling with iTunes a new file is created and added to the library.  Most of the old data are preserved but some such as date added are created when the track is added.
Using a third party tool may achieve what you want because the new file could overwrite the old one.  I recall using a third party tool to edit a mp3 and overwrite the old file.  iTunes was tricked into thinking the replacement was still the original file, but of course the edits were in place.  I can't make a specific application recommendation for bulk conversion where it will overwrite the old file.
I will regard this as a general iTunes question but in general if you are using beta software versions you should not be posting in the main iTunes forum.